Opt-in to persist model from /model (#15820)

packages/cli/src/ui/components/ModelDialog.test.tsx

@@ -47,7 +47,7 @@ describe('<ModelDialog />', () => {
   const mockGetHasAccessToPreviewModel = vi.fn();
 
   interface MockConfig extends Partial<Config> {
-    setModel: (model: string) => void;
+    setModel: (model: string, isTemporary?: boolean) => void;
     getModel: () => string;
     getPreviewFeatures: () => boolean;
     getHasAccessToPreviewModel: () => boolean;
@@ -89,9 +89,7 @@ describe('<ModelDialog />', () => {
   it('renders the initial "main" view correctly', () => {
     const { lastFrame } = renderComponent();
     expect(lastFrame()).toContain('Select Model');
-    expect(lastFrame()).toContain(
-      'Applies to this session and future Gemini CLI sessions.',
-    );
+    expect(lastFrame()).toContain('Remember model for future sessions: false');
     expect(lastFrame()).toContain('Auto');
     expect(lastFrame()).toContain('Manual');
   });
@@ -148,7 +146,10 @@ describe('<ModelDialog />', () => {
     stdin.write('\r');
     await waitForUpdate();
 
-    expect(mockSetModel).toHaveBeenCalledWith(DEFAULT_GEMINI_MODEL_AUTO);
+    expect(mockSetModel).toHaveBeenCalledWith(
+      DEFAULT_GEMINI_MODEL_AUTO,
+      true, // Session only by default
+    );
     expect(mockOnClose).toHaveBeenCalled();
   });
 
@@ -165,7 +166,29 @@ describe('<ModelDialog />', () => {
     stdin.write('\r');
     await waitForUpdate();
 
-    expect(mockSetModel).toHaveBeenCalledWith(DEFAULT_GEMINI_MODEL);
+    expect(mockSetModel).toHaveBeenCalledWith(DEFAULT_GEMINI_MODEL, true);
+    expect(mockOnClose).toHaveBeenCalled();
+  });
+
+  it('toggles persist mode with Tab key', async () => {
+    const { lastFrame, stdin } = renderComponent();
+
+    expect(lastFrame()).toContain('Remember model for future sessions: false');
+
+    // Press Tab to toggle persist mode
+    stdin.write('\t');
+    await waitForUpdate();
+
+    expect(lastFrame()).toContain('Remember model for future sessions: true');
+
+    // Select "Auto" (index 0)
+    stdin.write('\r');
+    await waitForUpdate();
+
+    expect(mockSetModel).toHaveBeenCalledWith(
+      DEFAULT_GEMINI_MODEL_AUTO,
+      false, // Persist enabled
+    );
     expect(mockOnClose).toHaveBeenCalled();
   });
 

packages/cli/src/ui/components/ModelDialog.tsx

@@ -32,6 +32,7 @@ interface ModelDialogProps {
 export function ModelDialog({ onClose }: ModelDialogProps): React.JSX.Element {
   const config = useContext(ConfigContext);
   const [view, setView] = useState<'main' | 'manual'>('main');
+  const [persistMode, setPersistMode] = useState(false);
 
   // Determine the Preferred Model (read once when the dialog opens).
   const preferredModel = config?.getModel() || DEFAULT_GEMINI_MODEL_AUTO;
@@ -62,6 +63,9 @@ export function ModelDialog({ onClose }: ModelDialogProps): React.JSX.Element {
           onClose();
         }
       }
+      if (key.name === 'tab') {
+        setPersistMode((prev) => !prev);
+      }
     },
     { isActive: true },
   );
@@ -157,13 +161,13 @@ export function ModelDialog({ onClose }: ModelDialogProps): React.JSX.Element {
       }
 
       if (config) {
-        config.setModel(model);
+        config.setModel(model, persistMode ? false : true);
         const event = new ModelSlashCommandEvent(model);
         logModelSlashCommand(config, event);
       }
       onClose();
     },
-    [config, onClose],
+    [config, onClose, persistMode],
   );
 
   let header;
@@ -213,9 +217,15 @@ export function ModelDialog({ onClose }: ModelDialogProps): React.JSX.Element {
         />
       </Box>
       <Box marginTop={1} flexDirection="column">
-        <Text color={theme.text.secondary}>
-          Applies to this session and future Gemini CLI sessions.
-        </Text>
+        <Box>
+          <Text color={theme.text.primary}>
+            Remember model for future sessions:{' '}
+          </Text>
+          <Text color={theme.text.secondary}>
+            {persistMode ? 'true' : 'false'}
+          </Text>
+        </Box>
+        <Text color={theme.text.secondary}>(Press Tab to toggle)</Text>
       </Box>
       <Box marginTop={1} flexDirection="column">
         <Text color={theme.text.secondary}>

packages/core/src/config/config.test.ts

@@ -1630,19 +1630,19 @@ describe('Config getHooks', () => {
       expect(config.getActiveModel()).toBe(originalModel);
     });
 
-    it('should call onModelChange when a new model is set', () => {
+    it('should call onModelChange when a new model is set and should persist', () => {
       const onModelChange = vi.fn();
       const config = new Config({
         ...baseParams,
         onModelChange,
       });
 
-      config.setModel(DEFAULT_GEMINI_MODEL);
+      config.setModel(DEFAULT_GEMINI_MODEL, false);
 
       expect(onModelChange).toHaveBeenCalledWith(DEFAULT_GEMINI_MODEL);
     });
 
-    it('should NOT call onModelChange when a new model is set as a fallback', () => {
+    it('should NOT call onModelChange when a new model is temporary', () => {
       const onModelChange = vi.fn();
       const config = new Config({
         ...baseParams,

packages/core/src/config/config.ts

@@ -909,13 +909,13 @@ export class Config {
     return this.model;
   }
 
-  setModel(newModel: string, isFallbackModel: boolean = false): void {
+  setModel(newModel: string, isTemporary: boolean = true): void {
     if (this.model !== newModel || this._activeModel !== newModel) {
       this.model = newModel;
       // When the user explicitly sets a model, that becomes the active model.
       this._activeModel = newModel;
       coreEvents.emitModelChanged(newModel);
-      if (this.onModelChange && !isFallbackModel) {
+      if (this.onModelChange && !isTemporary) {
         this.onModelChange(newModel);
       }
     }